Adaptive co-phasing for beamforming using co-phasing matrices for wireless communications

ABSTRACT

A network node, wireless device and methods for co-phasing for beamforming using co-phasing matrices for wireless communications are provided. In one example, a network node for co-phasing in beamforming for transmissions is provided. The network node includes processing circuitry including a processor and a memory where the memory contains instructions executable by the processor to configure the network node to: obtain co-phasing information associated with a wireless device, generate at least two co-phasing matrices based on the co-phasing information, and apply the at least two co-phasing matrices to at least two resource structures.

TECHNICAL FIELD

Wireless communication and in particular to applying co-phasing forbeamformed transmissions with an active antenna system.

BACKGROUND

Active antenna system (AAS) is one of several technologies included in4^(th) Generation Long Term Evolution (4G LTE) and 5^(th) Generation NewRadio (5G NR) standards to help enhance the wireless network performanceand capacity by using full dimension multiple-input and multiple-output(FD-MIMO) and massive MIMO. Some AAS systems consist of two-dimensionalantenna elements array with M rows, N columns and K polarizations (whereK=2 in case of cross-polarization) as illustrated in FIG. 1.

The codebook-based precoding in AAS is based on a set of predefinedprecoding matrices, W. The precoding matrix indication (PMI) may beselected by a wireless device with Downlink Channel State InformationReference Signaling (DL CSI-RS) or by the network node, e.g., eNodeB(eNB) in Long Term Evaluation (LTE), g Node B (gNB) in New Radio (NR),etc., with uplink (UL) reference signals. The precoding matrix W may befurther described as, for example, a two-stage precoding structure asfollows:

W=W ₁ W ₂  (1)

where W₁ is the first stage precoding structure and may be described asa codebook and consists essentially of a group of 2D grid-of-beams(GoB). W₁ may be characterized as:

$W_{1} = \begin{bmatrix}{w_{h} \otimes w_{v}} & 0 \\0 & {w_{h} \otimes w_{v}}\end{bmatrix}$

where, w_(h) and w_(v) are precoding vectors selected from anover-sampled Discrete Fourier Transform (DFT) for a horizontal directionand a vertical direction, respectively, and may be expressed by

$w_{v} = {\frac{1}{\sqrt{M}}\left\lbrack {1,e^{\frac{j2\pi v}{MO_{1}}},\ldots\mspace{14mu},e^{\frac{j2\pi mv}{MO_{1}}},\ldots\mspace{14mu},\ e^{\frac{j2{\pi{({M - 1})}}v}{MO_{1}}}} \right\rbrack}^{T}$$w_{h} = {\frac{1}{\sqrt{N}}\left\lbrack {1,e^{\frac{j\; 2\;\pi\; h}{{NO}_{2}}},\ldots\mspace{14mu},e^{\frac{j2\pi mv}{{NO}_{2}}},\ldots\mspace{14mu},\ e^{\frac{j2{\pi{({M - 1})}}h}{{NO}_{2}}}} \right\rbrack}^{T}$

where, O₁, O₂ are the over-sampling rates in vertical and horizontaldirections, respectively.

The second stage of the precoding matrix, denoted as W₂, is used forbeam selection within the group of 2D GoBs as well as the associatedco-phasing between two polarizations. Therefore, the AAS performance maynot only depend on codebook W₁, but may also depend on the co-phasingmatrix of W₂.

Closed-Loop Co-Phasing

In 3rd Generation Partnership Project (3GPP, a standardizationorganization), closed-loop co-phasing is defined in multiple-inputmultiple-output (MIMO) type of “CLASS A” and “TypeI-SinglePanel”. Thatis:

$W_{2} = {\frac{1}{\sqrt{2}}\begin{bmatrix}1 \\\varphi_{l}\end{bmatrix}}$

For single layer transmission is used as the single co-phasing matrix.Transmission layer may refer to a spatial layer used during transmissionwhere the number of spatial layers may be limited by the number ofantennas at the network node and/or wireless device.

For dual layer transmission

$W_{2} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}$

is used as the single co-phasing matrix, where φ_(l) is the co-phasingfactor that may be determined by the wireless device reported widebandor subband co-phasing index l, denoted by

φ_(l) =e ^(jπl/2)

The co-phasing is based on the wireless device's co-phasing indexreport. One issue from this arrangement may be that the co-phasing isfixed and might lead to an imbalance among two transmission layers suchas a power or gain imbalance between transmission layers. For example,

$W_{2} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}$

is optimized for the first transmission layer and not the secondtransmission layer such that the first transmission layer may havebetter performance characteristics (e.g., gain) than the secondtransmission layer after the co-phasing matrix is applied, therebyleading to poor overall performance. In some cases, a penalty may beapplied to the second transmission layer to compensate for theco-phasing matrix “favoring” the first transmission layer, i.e.,providing at least one better performance characteristics to the firsttransmission layer when compared to the second transmission layer.

SUMMARY

Some embodiments advantageously provide a method, system, wirelessdevice and network node for co-phasing for beamforming fortransmissions.

One or more embodiments provide a network node, wireless device, systemsand methods for co-phasing for beamforming using co-phasing matrices forwireless communications.

According to one aspect, a network node for co-phasing in beamformingfor transmissions by a cross-polarization antenna array is provided. Thenetwork node includes processing circuitry including a processor and amemory. The memory contains instructions executable by the processor toconfigure the network node to: obtain co-phasing information associatedwith a wireless device; generate at least two co-phasing matrices basedon the co-phasing information; and apply the at least two co-phasingmatrices to at least two resource structures.

According to this aspect, in some embodiments, the co-phasinginformation is obtained from a co-phasing index report associated withthe wireless device. In some embodiments, the co-phasing index reportindicates a value of a co-phasing factor used to generate the at leasttwo co-phasing matrices. In some embodiments, the co-phasing informationis obtained based on at least one uplink reference signal associatedwith the wireless device. In some embodiments, a first column of a firstmatrix of the at least two co-phasing matrices provides higher gain fora first transmission layer than a gain provided by a second column of afirst matrix for a second transmission layer, the first transmissionlayer being different from the second transmission layer. In someembodiments, a second column of a second matrix of the at least twoco-phasing matrices provides higher gain for the second transmissionlayer than the gain provided by a first column of the second matrix forthe first transmission layer. In some embodiments, the at least twoco-phasing matrices are generated by a phase rotation upon a base matrixformed with a co-phasing factor obtained from the co-phasinginformation. In some embodiments, the base matrix for single-layertransmission is formed by a 2×1 vector, a first element of which isequal to 1, and a second element of which is equal to the co-phasingfactor. In some embodiments, the base matrix for dual-layer transmissionis formed by a 2×2 matrix, a first element of a first column being equalto 1, a second element of the first column being equal to the co-phasingfactor, a first element of a second column being equal to 1, and asecond element of the second column being the negative of the co-phasingfactor. In some embodiments, in case of more than two layertransmission, the more than two layers are divided into dual-layergroups for even number of layers, and are divided into dual layer groupsplus an additional layer for odd number of layers, and wherein at leasttwo matrices are generated per dual layer group. In some embodiments, iftwo co-phasing matrices are generated for two layers transmission,columns of the second matrix correspond to interchanged columns of thefirst matrix. In some embodiments, if four co-phasing matrices are to begenerated for two layers transmission, then columns of a third matrixcorrespond to interchanged columns of a first matrix, and columns of afourth matrix correspond to interchanged columns of a second matrix. Insome embodiments, the applying of the at least two co-phasing matricesto the one of the at least two resource structures includes applying arespective matrix of the at least two co-phasing matrices to one of arespective resource structure of the at least two resource structures.The at least two resource structures are one of at least two physicalresource blocks, PRBs, and at least two resource elements, REs In someembodiments, the applying of the at least two co-phasing matrices to atleast two resource structures is transparent to the wireless devicereceiving at least one transmission. In some embodiments, a sequence ofapplying the at least two co-phasing matrices to one of the at least tworesource structures is chosen randomly by the network node. In someembodiments, a granularity of the applying of the at least twoco-phasing matrices to the one of the at least two resource structuresis indicated to the wireless device receiving at last one transmission.In some embodiments, a sequence of applying the at least two co-phasingmatrices to the one of the at least two resources structures ispre-selected for both the network node and the wireless device.

According to another aspect, a method for a network node for co-phasingin beamforming for transmissions by a cross-polarization antenna arrayis provided. The method includes: obtaining co-phasing informationassociated with a wireless device; generating at least two co-phasingmatrices based on the co-phasing information; and applying the at leasttwo co-phasing matrices to one of at least two resource structures.

According to this aspect, in some embodiments, the co-phasinginformation is obtained from a co-phasing index report associated withthe wireless device. In some embodiments, the co-phasing index reportindicates a value of a co-phasing factor used to generate the at leasttwo co-phasing matrices. In some embodiments, the co-phasing informationis obtained based on at least one uplink reference signal associatedwith the wireless device. In some embodiments, a first column of a firstmatrix of the at least two co-phasing matrices provides higher gain fora first transmission layer than a gain provided by a second column of afirst matrix for a second transmission layer, the first transmissionlayer being different from the second transmission layer. In someembodiments, a second column of a second matrix of the at least twoco-phasing matrices provides higher gain for the second transmissionlayer than the gain provided by a first column of a second matrix forthe first transmission layer. In some embodiments, the at least twoco-phasing matrices are generated by a phase rotation upon a base matrixformed with a co-phasing factor obtained from the co-phasinginformation. In some embodiments, the base matrix for single-layertransmission is formed by a 2×1 vector, a first element of which isequal to 1, and a second element of which is equal to the co-phasingfactor. In some embodiments, the base matrix for dual-layer transmissionis formed by a 2×2 matrix, a first element of a first column being equalto 1, a second element of the first column being equal to the co-phasingfactor, a first element of a second column being equal to 1, and asecond element of the second column being the negative of the co-phasingfactor. In some embodiments, in case of more than two layertransmission, the more than two layers are divided into dual-layergroups for even number of layers, and are divided into dual layer groupsplus an additional layer for odd number of layers, and wherein at leasttwo co-phasing matrices are generated per dual layer group. In someembodiments, if two co-phasing matrices are generated for two layerstransmission, columns of the second matrix correspond to interchangedcolumns of the first matrix. In some embodiments, if four co-phasingmatrices are to be generated for two layers transmission, then columnsof a third matrix correspond to interchanged columns of a first matrix,and columns of a fourth matrix correspond to interchanged columns of asecond matrix. In some embodiments, the applying of the at least twoco-phasing matrices to the one of the at least two resource structuresincludes applying a respective matrix of the at least two matrices toone of a respective resource structure of the at least two resourcestructures. The at least two resource structures are one of at least twophysical resource blocks, PRBs, and at least two resource elements, REs.In some embodiments, the applying of the at least two co-phasingmatrices to at least two resource structures is transparent to thewireless device receiving at least one transmission. In someembodiments, a sequence of applying the at least two co-phasing matricesto one of the at least two resource structures is chosen randomly by thenetwork node. In some embodiments, a granularity of the applying of theat least two co-phasing matrices to the one of the at least two resourcestructures is indicated to the wireless device receiving at least onetransmission. In some embodiments, a sequence of applying the at leasttwo co-phasing matrices to the one of the at least two resourcestructures is pre-selected for both the network node and the wirelessdevice.

According to yet another aspect, a wireless device for receivingtransmissions is provided. The wireless device includes processingcircuitry including a processor and a memory. The memory containsinstructions executable by the processor to configure the wirelessdevice to: one of provide co-phasing information and signal at least oneuplink reference signal for determining co-phasing information; receiveat least one transmission that is based on at least two co-phasingmatrices applied to one of at least two resource structures, the atleast two co-phasing matrices being based on the one of providedco-phasing information and signaled at least one uplink referencesignal; and process the at least one transmission.

According to this aspect, in some embodiments, the provided co-phasinginformation indicates a value of a co-phasing factor used to generatethe at least two co-phasing matrices. In some embodiments, a firstcolumn of a first matrix of the at least two co-phasing matricesprovides higher gain for a first transmission layer than a gain providedby a second column of the first matrix for a second transmission layer,the first transmission layer being different from the secondtransmission layer. In some embodiments, a second column of a secondmatrix of the at least two co-phasing matrices provides higher gain forthe second transmission layer than the gain provided by a first columnof the second matrix for the first transmission layer. In someembodiments, a respective matrix of the at least two co-phasing matricesis associated with one of a respective resource structure of the atleast two resource structures. The at least two resource structures areone of at least two physical resource blocks, PRBs, and at least tworesource elements, REs. In some embodiments, the at least two co-phasingmatrices are transparent to the wireless device receiving the at leastone transmission. In some embodiments, the memory contains furtherinstructions executable by the processor to configure the wirelessdevice to receive an indication of a granularity of the at least twoco-phasing matrices with respect to the one of the at least two resourcestructures.

According to another embodiment, a method for a wireless device forreceiving transmissions is provided. The method includes one ofproviding co-phasing information and signaling at least one uplinkreference signal for determining co-phasing information. The method alsoincludes receiving at least one transmission that is based on at leasttwo co-phasing matrices applied to one of at least two resourcestructures, the at least two co-phasing matrices being based on the oneof provided co-phasing information and signaled at least one uplinkreference signal. The method further includes processing the at leastone transmission.

According to this aspect, in some embodiments, the provided co-phasinginformation indicates a value of a co-phasing factor used to generatethe at least two co-phasing matrices. In some embodiments, a firstcolumn of a first matrix of the at least two co-phasing matricesprovides higher gain for a first transmission layer than a gain providedby a second column of the first matrix for a second transmission layer,the first transmission layer being different from the secondtransmission layer. In some embodiments, a second column of a secondmatrix of the at least two co-phasing matrices provides higher gain forthe second transmission layer than the gain provided by a first columnof the second matrix for the first transmission layer. In someembodiments, a respective matrix of the at least two co-phasing matricesis associated with one of a respective resource structures of the atleast two resource structures. The at least two resource structures areone of at least two physical resource blocks, PRBs, and at least tworesource elements, REs. In some embodiments, the at least two co-phasingmatrices are transparent to the wireless device receiving the at leastone transmission. In some embodiments, the method further includesreceiving an indication of a granularity of the at least two co-phasingmatrices with respect to the one of the at least two resourcestructures.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present embodiments, and theattendant advantages and features thereof, will be more readilyunderstood by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is a diagram of a two-dimensional cross-polarized antenna elementarray;

FIG. 2 is an exemplary system for co-phasing for beamforming inaccordance with the principles of the disclosure;

FIG. 3 is a flowchart of an exemplary process in a network node ofco-phasing for generating and applying co-phasing matrices in accordancewith the principles of the disclosure;

FIG. 4 is a flowchart of an exemplary process in a wireless device forfacilitating transmission based on co-phasing matrices; and

FIG. 5 is a diagram illustrating the performance of semi-closed-loopco-phasing with respect to existing closed-loop co-phasing and existingsemi-open-loop co-phasing.

DETAILED DESCRIPTION

The disclosure helps solve at least some of the problems with existingsystems by providing a co-phasing method and arrangements, at least inpart, by providing adaptive co-phasing that may be transparent to thewireless device such as transparent in resource structure, e.g.,Physical Resource Block (PRB), granularity, and that can be used withwireless devices operating using wireless communication standards suchas 3GPP Release 13 and lower. For example, semi-open-loop co-phasing,described below, suffers from fixed co-phasing that may lead to one ormore issues.

Semi-Open-Loop Co-Phasing

In 3GPP, a semi-open-loop (“semiOpenLoop”) is described as followsspecifically for dual-layer transmission:

For dual layer transmission:

${W_{2} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}},{\varphi_{i} = e^{j{{\pi{({imod2})}}/2}}}$

where φ_(i) is the co-phasing factor determined by a network node (e.g.,base station, eNB, gNB, etc.) for the i-th vector of symbols from thetransmission layer mapping. That means that:

If  imod2 = 0 $W_{2} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\1 & {- 1}\end{bmatrix}}$ If  imod2 = 1 $W_{2} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\j & {- j}\end{bmatrix}}$

However, while the network node may determine the co-phasing factor inthe semi-open-loop co-phasing, the co-phasing factor is not based on awireless device's co-phasing index report. Instead, the co-phasingfactor in semi-open-loop co-phasing is based on two fixed co-phasingfactors toggled in a granularity of per resource structure such asresource element (RE). Some problems that may result from theseco-phasing factors are:

-   -   1) The co-phasing factors rely on wireless device capability of        semi-open-loop co-phasing of particular wireless communication        standard(s) such as 3GPP Release 14. Therefore, the co-phasing        factors may not be used with wireless devices operating on        certain wireless communication standards such as 3GPP Release 13        and lower.    -   2) The co-phasing factors are equivalent to having two fixed        co-phasing factors of 0° and 90°, which may not be adaptive to        the phase difference of two polarizations.

Unlike existing systems that rely on fixed co-phasing, the disclosureteaches adaptive co-phasing based on co-phasing information. In one ormore examples, the co-phasing is performed in an alternated manner inresource structure granularity such as PRBs or Resource Elements (REs)granularity using an obtained co-phasing factor. Further, the providedco-phasing method/process is adaptive to the real or actual phasedifference of two polarizations, i.e., “adaptive” may correspond totaking into account actual phase differences, which may be indicated orbased on the co-phasing information. Furthermore, the providedco-phasing method/process helps to balance channel quality amongtransmission layers to achieve higher overall beamforming gain andbetter overall performance.

Before describing in detail exemplary embodiments, it is noted that theembodiments reside primarily in combinations of apparatus components andprocessing steps related to co-phasing for beamforming. Accordingly,components have been represented where appropriate by conventionalsymbols in the drawings, showing only those specific details that arepertinent to understanding the embodiments so as not to obscure thedisclosure with details that will be readily apparent to those ofordinary skill in the art having the benefit of the description herein.

As used herein, relational terms, such as “first,” “second,” “top” and“bottom,” and the like, may be used solely to distinguish one entity orelement from another entity or element without necessarily requiring orimplying any physical or logical relationship or order between suchentities or elements. The terminology used herein is for the purpose ofdescribing particular embodiments only and is not intended to belimiting of the concepts described herein. As used herein, the singularforms “a”, “an” and “the” are intended to include the plural forms aswell, unless the context clearly indicates otherwise. It will be furtherunderstood that the terms “comprises,” “comprising,” “includes” and/or“including” when used herein, specify the presence of stated features,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof.

The term “network node” used herein can be any kind of network nodecomprised in a radio network which may further comprise any of basestation (BS), radio base station, base transceiver station (BTS), basestation controller (BSC), radio network controller (RNC), evolved Node B(eNB or eNodeB), Node B, multi-standard radio (MSR) radio node such asMSR BS, relay node, donor node controlling relay, radio access point(AP), transmission points, transmission nodes, Remote Radio Unit (RRU)Remote Radio Head (RRH), nodes in distributed antenna system (DAS) etc.

The term “wireless device” may be a radio communication device, wirelessdevice endpoint, mobile endpoint, device endpoint, sensor device, targetdevice, device-to-device wireless device, user equipment (UE), machinetype wireless device or wireless device capable of machine to machinecommunication, a sensor equipped with wireless device, tablet, mobileterminal, mobile telephone, laptop, computer, appliance, automobile,smart phone, laptop embedded equipped (LEE), laptop mounted equipment(LME), USB dongle and customer premises equipment (CPE), among otherdevices that can communicate radio or wireless signals as are known inthe art.

An indication generally may explicitly and/or implicitly indicate theinformation it represents and/or indicates. Implicit indication may forexample be based on position and/or resource used for transmission.Explicit indication may for example be based on a parametrization withone or more parameters, and/or one or more index or indices, and/or oneor more bit patterns representing the information. It may in particularbe considered that control signaling as described herein, based on theutilized resource sequence, implicitly indicates the control signalingtype.

It may be considered for cellular communication there is provided atleast one uplink (UL) connection and/or channel and/or carrier and atleast one downlink (DL) connection and/or channel and/or carrier, e.g.,via and/or defining a cell, which may be provided by a network node, inparticular a base station, gNB or eNodeB. An uplink direction may referto a data transfer direction from a terminal to a network node, e.g.,base station, gNB and/or relay station. A downlink direction may referto a data transfer direction from a network node, e.g., base station,gNB and/or relay node, to a terminal. UL and DL may be associated todifferent frequency resources, e.g., carriers and/or spectral bands. Acell may comprise at least one uplink carrier and at least one downlinkcarrier, which may have different frequency bands. A network node, e.g.,a base station, gNB or eNodeB, may be adapted to provide and/or defineand/or control one or more cells, e.g., a PCell and/or a LA cell.

Configuring a terminal or wireless device or node may involveinstructing and/or causing the wireless device or node to change itsconfiguration, e.g., at least one setting and/or register entry and/oroperational mode. A terminal or wireless device or node may be adaptedto configure itself, e.g., according to information or data in a memoryof the terminal or wireless device. Configuring a node or terminal orwireless device by another device or node or a network may refer toand/or comprise transmitting information and/or data and/or instructionsto the wireless device or node by the other device or node or thenetwork, e.g., allocation data (which may also be and/or compriseconfiguration data) and/or scheduling data and/or scheduling grants.Configuring a terminal may include sending allocation/configuration datato the terminal indicating which modulation and/or encoding to use. Aterminal may be configured with and/or for scheduling data and/or touse, e.g., for transmission, scheduled and/or allocated uplinkresources, and/or, e.g., for reception, scheduled and/or allocateddownlink resources. Uplink resources and/or downlink resources may bescheduled and/or provided with allocation or configuration data.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It willbe further understood that terms used herein should be interpreted ashaving a meaning that is consistent with their meaning in the context ofthis specification and the relevant art and will not be interpreted inan idealized or overly formal sense unless expressly so defined herein.

In embodiments described herein, the joining term, “in communicationwith” and the like, may be used to indicate electrical or datacommunication, which may be accomplished by physical contact, induction,electromagnetic radiation, radio signaling, infrared signaling oroptical signaling, for example. One having ordinary skill in the artwill appreciate that multiple components may interoperate andmodifications and variations are possible of achieving the electricaland data communication.

Referring now to drawing figures in which like reference designatorsrefer to like elements, there is shown in FIG. 2 an exemplary system forco-phasing for beamforming. In one or more embodiments, the co-phasingfor beamforming is performed in an Active Antenna System (AAS). System10 includes one or more network nodes 12 and one or more wirelessdevices 14, in communication with each other via one or morecommunication networks, paths and/or links using one or morecommunication protocols such as LTE or NR based protocols.

Network node 12 includes transmitter 16 and receiver 18 forcommunicating with wireless devices 14, other network nodes 12 and/orother entities in system 10. In one or more embodiments, transmitter 16and receiver 18 includes or is replaced by one or more communicationinterfaces.

Network node 12 includes processing circuitry 20. Processing circuitry20 includes processor 22 and memory 24. In addition to a traditionalprocessor and memory, processing circuitry 20 may comprise integratedcircuitry for processing and/or control, e.g., one or more processorsand/or processor cores and/or FPGAs (Field Programmable Gate Array)and/or ASICs (Application Specific Integrated Circuitry). Processor 22may be configured to access (e.g., write to and/or reading from) memory24, which may include any kind of volatile and/or nonvolatile memory,e.g., cache and/or buffer memory and/or RAM (Random Access Memory)and/or ROM (Read-Only Memory) and/or optical memory and/or EPROM(Erasable Programmable Read-Only Memory). Such memory 24 may beconfigured to store code executable by processor 22 and/or other data,e.g., data pertaining to communication, e.g., configuration and/oraddress data of nodes, etc.

Processing circuitry 20 may be configured to control any of the methodsand/or processes described herein and/or to cause such methods,signaling and/or processes to be performed, e.g., by network node 12.Processor 22 corresponds to one or more processors 22 for performingnetwork node 12 functions described herein. Network node 12 includesmemory 24 that is configured to store data, programmatic software codeand/or other information described herein. In one or more embodiments,memory 24 is configured to store co-phasing code 26. For example,co-phasing code 26 includes instructions that, when executed byprocessor 22, causes processor 22 to perform the signaling describeherein with respect to network node 12.

Wireless device 14 includes transmitter 28 and receiver 30 forcommunicating with network node 12, other wireless devices 14 and/orother entities in system 10. In one or more embodiments, transmitter 28and receiver 30 includes or is replaced by one or more communicationinterfaces.

Wireless device 14 includes processing circuitry 32. Processingcircuitry 32 includes processor 34 and memory 36. In addition to atraditional processor and memory, processing circuitry 32 may compriseintegrated circuitry for processing and/or control, e.g., one or moreprocessors and/or processor cores and/or FPGAs (Field Programmable GateArray) and/or ASICs (Application Specific Integrated Circuitry).Processor 34 may be configured to access (e.g., write to and/or readingfrom) memory 36, which may comprise any kind of volatile and/ornonvolatile memory, e.g., cache and/or buffer memory and/or RAM (RandomAccess Memory) and/or ROM (Read-Only Memory) and/or optical memoryand/or EPROM (Erasable Programmable Read-Only Memory). Such memory 36may be configured to store code executable by processor 34 and/or otherdata, e.g., data pertaining to communication, e.g., configuration and/oraddress data of nodes, etc.

Processing circuitry 32 may be configured to control any of the methodsand/or processes described herein and/or to cause such methods,signaling and/or processes to be performed, e.g., by wireless device 14.Processor 34 corresponds to one or more processors 34 for performingwireless device 14 functions described herein. Wireless device 14includes memory 36 that is configured to store data, programmaticsoftware code and/or other information described herein. In one or moreembodiments, memory 36 is configured to store processing code 38. Forexample, processing code 38 includes instructions that, when executed byprocessor 34, causes processor 34 to perform the processes describedherein with respect to wireless device 14.

Note further that functions described herein as being performed by awireless device 14 or a network node 12 may be distributed over aplurality of wireless devices 14 and/or network nodes 12. In otherwords, it is contemplated that the functions of the network node 12 andwireless device 14 described herein are not limited to performance by asingle physical device and, in fact, can be distributed among severalphysical devices locally or across a network cloud such as a backhaulnetwork, core network and/or the Internet.

FIG. 3 is a flowchart of an exemplary process in a network node ofco-phasing code for generating and applying co-phasing matrices.Processing circuitry 20 is configured to obtain co-phasing informationassociated with a wireless device 14, as described herein (Block S100).In one or more embodiments, the obtaining of information includesobtaining at least one co-phasing factor as described below. Thus, theinformation may include at least one co-phasing factor. In one or moreembodiments, the co-phasing information is obtained from the wirelessdevice 14, another network node 12 and/or the core network.

Obtaining at Least One Co-Phasing Factor

For wireless devices 14 operating using a wireless standard such as 3GPPRelease 13, at least one co-phasing factor may be obtained by networknode 12 using the wireless device's co-phasing index report. Forwireless devices 14 operating using a wireless device standard such as3GPP Release lower than Release 13, the at least one co-phasing factormay be estimated at network node 12 (e.g., eNB, gNB, base station, etc.)by using uplink (UL) reference signals (e.g., sounding reference signal,or PUSCH demodulation reference signal) received from wireless device14. In one or more embodiments, network node 12 uses a wireless devicespecific reference signal for the estimation of at least one co-phasingfactor. For example, network node 12 can estimate the co-phasing factorbased on one or more UL references signals received from wireless device14.

Processing circuitry 20 is configured to generate at least twoco-phasing matrices based on the co-phasing information, as describedherein (Block S102). For example, the semi-closed-loop co-phasingdescried below may be used to generate at least two co-phasing matricesor a set of co-phasing matrices.

Semi-Closed-Loop Co-Phasing

The semi-closed-loop co-phasing method may include generating a set ofco-phasing matrices by, in one example, introducing additional phaserotations upon a base matrix constructed from the obtained co-phasingfactor expressed by:

In 1-layer transmission:

$W_{2}^{(i)} = {{\frac{1}{\sqrt{2}}\begin{bmatrix}1 & 0 \\0 & e^{j2\pi{i/N_{c}}}\end{bmatrix}}\begin{bmatrix}1 \\\varphi_{l}\end{bmatrix}}$

In 2-layer transmission:

$W_{2}^{(i)} = {{\frac{1}{2}\begin{bmatrix}1 & 0 \\0 & e^{j2\pi{i/N_{c}}}\end{bmatrix}}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}$

where N_(c) is the total number of phase rotations to be applied and W₂^((i)) are the associated i-th co-phasing matrices.In one example, two co-phasing matrices for N_(c)=2 are given asfollows:

${W_{2}^{(0)} = {{{\frac{1}{2}\begin{bmatrix}1 & 0 \\0 & e^{j2\pi \times {0/2}}\end{bmatrix}}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}}},{and}$ $W_{2}^{(1)} = {{{\frac{1}{2}\begin{bmatrix}1 & 0 \\0 & e^{j2\pi \times {1/2}}\end{bmatrix}}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\{- \varphi_{l}} & \varphi_{l}\end{bmatrix}}}$

In another example, four co-phasing matrices for N_(c)=4 are given asfollows:

${W_{2}^{(0)} = {{{\frac{1}{2}\begin{bmatrix}1 & 0 \\0 & e^{j2\pi \times {0/4}}\end{bmatrix}}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}}},{w_{2}^{(1)} = {{{\frac{1}{2}\begin{bmatrix}1 & 0 \\0 & e^{j2\pi \times {1/4}}\end{bmatrix}}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\{j\;\varphi_{l}} & {{- j}\;\varphi_{l}}\end{bmatrix}}}},{W_{2}^{(2)} = {{{\frac{1}{2}\begin{bmatrix}1 & 0 \\0 & e^{j2\pi \times {2/4}}\end{bmatrix}}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}}},{and}$ $w_{2}^{(3)} = {{{\frac{1}{2}\begin{bmatrix}1 & 0 \\0 & e^{j2\pi \times {3/4}}\end{bmatrix}}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}} = {{\frac{1}{2}\begin{bmatrix}1 & 1 \\{j\;\varphi_{l}} & {{- j}\;\varphi_{l}}\end{bmatrix}}.}}$

In case of more than two transmission layers, in one or moreembodiments, the transmission layers are divided into several 2-layergroups and possibly one 1-layer group. The co-phasing matrix generationfor the 2-layer case and 1-layer case are applied to each transmissionlayer group accordingly.

While two co-phasing matrices are discussed herein, the disclosure isequally applicable to the generation and use of more than two co-phasingmatrices. For example, the quantity of co-phasing matrices that aregenerated may be based on and/or correspond to a quantity of coefficientfactors reported by the wireless device 14. In another example, thequantity of co-phasing matrices that are generated may be based onand/or correspond to the quantity of transmission layers.

Processing circuitry 20 is configured to apply the at least twoco-phasing matrices to at least two resource structures (Block S104). Insome embodiments, the at least two resource structures includes at leasttwo physical resource blocks (PRBs), at least two resource elements(REs) and/or at least two other wireless communication protocol basedstructures for at least two radio resources.

In one or more embodiments, the generated co-phasing matrices areapplied alternately in a pre-defined granularity (e.g., appliedalternately to respective resource structures such as PRBs or REs suchthat one co-phasing matrix is applied to one PRB and another co-phasingmatrix is applied to another PRB, where this pattern continues for oneor more PRBs). For example, if the granularity is per PRB, W₂ ^((i)) isapplied to REs in an i-th scheduled PRB. If the granularity is per RE,W₂ ^((i)) is applied to an i-th RE in scheduled PRBs.

When constructing the precoding matrix, W₂ ^((i)) may be selectedaccording to the index of PRBs or REs if per PRB or per RE granularityis applied, for example

On even PRBs:

W ₂ =W ₂ ⁽⁰⁾

On Odd PRBs:

W ₂ =W ₂ ⁽¹⁾

Note that the sequence of applying the two or more co-phasing matricesmay be predefined for both the network node and the wireless device orrandomly chosen by the network node if the co-phasing is transparent tothe wireless device.

In one or more embodiments, each co-phasing matrix may be applied to arespective resource structure such as a PRB. For example, if fourco-phasing matrices are generated (i.e., W₂ ⁽⁰⁾, W₂ ⁽¹⁾, W₂ ⁽²⁾, W₂⁽³⁾), each co-phasing matrix is applied to a respective PRB of four PRBssuch that W₂ ⁽⁰⁾ is applied to a first PRB, W₂ ⁽¹⁾ is applied to asecond PRB, W₂ ⁽²⁾ is applied to a third PRB and W₂ ⁽³⁾ is applied to afourth PRB. In one or more embodiments, a co-phasing matrix is appliedto at least a portion of or all REs of the PRB.

FIG. 4 is a flowchart of an exemplary process in a wireless device 14 ofprocessing code 38 for facilitating transmission based on co-phasingmatrices. Processing circuitry 32 is configured to one of provideco-phasing information and signal at least one uplink reference signalfor determining co-phasing information, as described herein (BlockS106). Processing circuitry 32 is configured to receive at least onetransmission that is based on at least two co-phasing matrices appliedto at least two resource structures where the at least two co-phasingmatrices are based on the one of provided co-phasing information andsignaled at least one uplink reference signal, as described herein(Block S108). Processing circuitry 32 is configured to process the atleast one transmission, as described herein (Block S110).

Transparency for Wireless Device 14

For downlink (DL) beamforming on the physical downlink shared channelPDSCH, with a demodulation reference signal (e.g., Transmission Mode(TM) 8, TM9 and TM10), the wireless device 14 may perform channelestimation with the DMRS within a Physical Resource Block (PRB). In oneor more examples, with the co-phasing and per PRB granularity describedherein, a single co-phasing may be applied to all REs in one PRB. Theco-phasing may be estimated as part of channel estimation such thatthere may be little to no impact on wireless device's channel estimationand demodulation.

Transmission Layer Balance in a Two Co-Phasing Matrix Example

In the dual layer transmission case, the first column of a firstco-phasing matrix (i.e., W₂ ⁽⁰⁾ is for a first transmission layer. Forexample, two co-phasing matrices for N_(c)=2 are given as follows:

${W_{2}^{(0)} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}},{and}$ $W_{2}^{(1)} = {\frac{1}{2}\begin{bmatrix}1 & 1 \\\varphi_{l} & {- \varphi_{l}}\end{bmatrix}}$

The first (leftmost) column of W₂ ⁽⁰⁾, i.e.,

$\begin{matrix}1 \\\varphi_{l}\end{matrix},$

is for the first transmission layer. The second column of a secondco-phasing matrix (i.e., W₂ ⁽¹⁾) is for a second transmission layer.Using the example above, the second (rightmost) column of W₂ ⁽¹⁾, i.e.,

$\begin{matrix}1 \\\varphi_{l}\end{matrix},$

is for the second transmission layer. If the co-phasing of first columnof the first co-phasing matrix “favors” the first transmission layer ineven PRBs, then the second column of the second co-phasing matrix favorsthe second layer in odd PRBs. For example, in some embodiments, thefirst column is for the first layer transmission, which might causeinterference to the second layer, and the second column is for thesecond layer transmission, which might cause interference to the firstlayer. In one or more examples, “favors” may relate to gain such thatthe co-phasing of first column of the first co-phasing matrix favoringthe first transmission layer may indicate that the first co-phasing ofthe first column provides higher gain to the first transmission layerthan gain provided to the second transmission layer by the second columnof the first co-phasing matrix. In the example, above, the twotransmission layers may be considered well-balanced as the first(leftmost) column of the first co-phasing matrix favors or benefits thefirst transmission layer such as in terms of gain, while the second(rightmost) column of the second co-phasing matrix favors or benefitsthe second transmission layer such as in terms of gain. In other words,the overall gain and/or other transmission characteristic(s) ofrespective transmission layers may be equal to each other or within apredefined quantity of each other based on the application of theco-phasing matrices.

In case of more than two transmission layers, the transmission layerbalance per layer group may be improved over other possible solutions bya 2-layer co-phasing per layer group. For example, if the first andsecond co-phasing matrix are applied to the first layer group, and thethird and fourth co-phasing matrix are applied to the second layergroup, then the layer balance may be improved per layer group. In one ormore embodiments, the number of generated co-phasing matrices maycorrespond to a number of transmissions layers.

Performance

FIG. 5 is a diagram illustrating the performance of one or more examplesof the semi-closed-loop co-phasing (described herein) in per PRBgranularity compared with existing closed-loop co-phasing and existingsemi-open-loop co-phasing. In the Extended Pedestrian A model (EPAS)channel with 64 antenna ports (64Tx, where the array has a configurationof 4×8×2 antenna elements), FIG. 5 illustrates that the semi-closed-loopco-phasing, described herein, outperforms existing closed-loopco-phasing and existing semi-open-loop co-phasing with respect toPhysical Downlink Shared Channel (PDSCH) throughput (bits per second(bps)) and signal to noise ratio (SINR) in dB. This performance increasein the semi-closed-loop co-phasing when compared to existing co-phasingmay be at least in part due to the ability of the semi-closed-loopco-phasing to achieve layer balance by co-phasing toggling as well asadapt to an actual phase difference by obtained co-phasing factors.

Therefore, unlike existing systems that rely on fixed co-phasing thatmay lead to imbalance (e.g., gain imbalance) between transmissionlayers, the teachings of the disclosure advantageously provide fordynamic and/or adaptive co-phasing such as by obtaining and using aco-phasing factor for determining co-phasing matrices to apply, therebyhelping balance the transmission layers. For example, a first column ofa co-phasing matrix is to be applied to the first transmission layer andthe second column of the co-phasing matrix is for the secondtransmission layer. If the co-phasing of the first column favors thefirst transmission layer for even numbered PRBs, then the second columnmay favor the second transmission layer for odd numbered PRBs, therebyhelping balance at least one characteristics (e.g., gain) of the twotransmission layers. In some embodiments, “favor” may correspond toproviding a higher gain. In one or more embodiments, the co-phasingfactor may be updated based on an updated co-phasing factor.

A resource structure may generally represent a structure in time and/orfrequency domain, in particular representing a time interval and afrequency interval. A resource structure may comprise and/or becomprised of resource elements, and/or the time interval of a resourcestructure may comprise and/or be comprised of symbol time interval/s,and/or the frequency interval of a resource structure may compriseand/or be comprised of subcarrier/s. A resource element may beconsidered an example for a resource structure. A slot or mini-slot or aPhysical Resource Block (PRB) or parts thereof may be considered otherexamples of a resource structure. A resource structure may be associatedto a specific channel, e.g. a PUSCH or PUCCH, in particular resourcestructure smaller than a slot or PRB.

Examples of a resource structure in frequency domain comprise abandwidth or band, or a bandwidth part. A bandwidth part may be a partof a bandwidth available for a radio node for communicating, e.g. due tocircuitry and/or configuration and/or regulations and/or a standard. Abandwidth part may be configured or configurable to a radio node. Insome variants, a bandwidth part may be the part of a bandwidth used forcommunicating, e.g. transmitting and/or receiving, by a radio node. Thebandwidth part may be smaller than the bandwidth (which may be a devicebandwidth defined by the circuitry/configuration of a device, and/or asystem bandwidth, e.g. available for a RAN). It may be considered that abandwidth part comprises one or more resource blocks or resource blockgroups, in particular one or more PRBs or PRB groups. A bandwidth partmay pertain to, and/or comprise, one or more carriers. A resource poolor region or set may generally comprise one or a plurality (inparticular, two or a multiple of two larger than two) of resources orresource structures. A resource or resource structure may comprise oneor more resource elements (in particular, two or a multiple of twolarger than two), or one or more PRBs or PRB groups (in particular, twoor a multiple of two larger than two), which may be continuous infrequency.

As will be appreciated by one of skill in the art, the conceptsdescribed herein may be embodied as a method, data processing system,and/or computer program product. Accordingly, the concepts describedherein may take the form of an entirely hardware embodiment, an entirelysoftware embodiment or an embodiment combining software and hardwareaspects all generally referred to herein as a “circuit” or “module.”Furthermore, the disclosure may take the form of a computer programproduct on a tangible computer usable storage medium having computerprogram code embodied in the medium that can be executed by a computer.Any suitable tangible computer readable medium may be utilized includinghard disks, CD-ROMs, electronic storage devices, optical storagedevices, or magnetic storage devices.

Some embodiments are described herein with reference to flowchartillustrations and/or block diagrams of methods, systems and computerprogram products. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer program instructions. These computer program instructions maybe provided to a processor of a general purpose computer, specialpurpose computer, or other programmable data processing apparatus toproduce a machine, such that the instructions, which execute via theprocessor of the computer or other programmable data processingapparatus, create means for implementing the functions/acts specified inthe flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in a computerreadable memory or storage medium that can direct a computer or otherprogrammable data processing apparatus to function in a particularmanner, such that the instructions stored in the computer readablememory produce an article of manufacture including instruction meanswhich implement the function/act specified in the flowchart and/or blockdiagram block or blocks.

The computer program instructions may also be loaded onto a computer orother programmable data processing apparatus to cause a series ofoperational steps to be performed on the computer or other programmableapparatus to produce a computer implemented process such that theinstructions which execute on the computer or other programmableapparatus provide steps for implementing the functions/acts specified inthe flowchart and/or block diagram block or blocks. It is to beunderstood that the functions/acts noted in the blocks may occur out ofthe order noted in the operational illustrations. For example, twoblocks shown in succession may in fact be executed substantiallyconcurrently or the blocks may sometimes be executed in the reverseorder, depending upon the functionality/acts involved. Although some ofthe diagrams include arrows on communication paths to show a primarydirection of communication, it is to be understood that communicationmay occur in the opposite direction to the depicted arrows.

Computer program code for carrying out operations of the conceptsdescribed herein may be written in an object oriented programminglanguage such as Java® or C++. However, the computer program code forcarrying out operations of the disclosure may also be written inconventional procedural programming languages, such as the “C”programming language. The program code may execute entirely on theuser's computer, partly on the user's computer, as a stand-alonesoftware package, partly on the user's computer and partly on a remotecomputer or entirely on the remote computer. In the latter scenario, theremote computer may be connected to the user's computer through a localarea network (LAN) or a wide area network (WAN), or the connection maybe made to an external computer (for example, through the Internet usingan Internet Service Provider).

Many different embodiments have been disclosed herein, in connectionwith the above description and the drawings. It will be understood thatit would be unduly repetitious and obfuscating to literally describe andillustrate every combination and subcombination of these embodiments.Accordingly, all embodiments can be combined in any way and/orcombination, and the present specification, including the drawings,shall be construed to constitute a complete written description of allcombinations and subcombinations of the embodiments described herein,and of the manner and process of making and using them, and shallsupport claims to any such combination or subcombination.

It will be appreciated by persons skilled in the art that theembodiments described herein are not limited to what has beenparticularly shown and described herein above. In addition, unlessmention was made above to the contrary, it should be noted that all ofthe accompanying drawings are not to scale. A variety of modificationsand variations are possible in light of the above teachings withoutdeparting from the scope of the following claims.

1. A network node for adaptive co-phasing in an Active Antenna System,AAS, for transmissions by a cross-polarization antenna array, thenetwork node comprising processing circuitry including a processor and amemory (24), the memory containing instructions executable by theprocessor to configure the network node to: obtain co-phasinginformation associated with a wireless device; generate at least twoco-phasing matrices based on the co-phasing information; and apply theat least two co-phasing matrices to at least two resource structures,the at least two resource structures being one of at least two physicalresource blocks, PRBs, and at least two resource elements, REs.
 2. Thenetwork node of claim 1, wherein the co-phasing information is obtainedfrom a co-phasing index report associated with the wireless device. 3.The network node of claim 2, wherein the co-phasing index reportindicates a value of a co-phasing factor used to generate the at leasttwo co-phasing matrices.
 4. The network node of claim 1, wherein theco-phasing information is obtained based on at least one uplinkreference signal associated with the wireless device.
 5. The networknode of claim 1, wherein a first column of a first matrix of the atleast two co-phasing matrices provides higher gain for a firsttransmission layer than a gain provided by a second column of the firstmatrix for a second transmission layer, the first transmission layerbeing different from the second transmission layer.
 6. (canceled)
 7. Thenetwork node of claim 1, wherein the at least two co-phasing matricesare generated by a phase rotation upon a base matrix formed with aco-phasing factor obtained from the co-phasing information. 8.-15.(canceled)
 16. The network node of claim 1, wherein a granularity of theapplying of the at least two co-phasing matrices to the one of the atleast two resource structures is indicated to the wireless devicereceiving at last one transmission.
 17. (canceled)
 18. A method for anetwork node for adaptive co-phasing in an Active Antenna System, AAS,for transmissions by a cross-polarization antenna array, the methodcomprising: obtaining co-phasing information associated with a wirelessdevice; generating at least two co-phasing matrices based on theco-phasing information; and applying the at least two co-phasingmatrices to one of at least two resource structures, the at least tworesource structures being one of at least two physical resource blocks,PRBs, and at least two resource elements, REs.
 19. The method of claim18, wherein the co-phasing information is obtained from a co-phasingindex report associated with the wireless device.
 20. The method ofclaim 19, wherein the co-phasing index report indicates a value of aco-phasing factor used to generate the at least two co-phasing matrices.21. The method of claim 18, wherein the co-phasing information isobtained based on at least one uplink reference signal associated withthe wireless device.
 22. The method of claim 18, wherein a first columnof a first matrix of the at least two co-phasing matrices provideshigher gain for a first transmission layer than a gain provided by asecond column of the first matrix for a second transmission layer, thefirst transmission layer being different from the second transmissionlayer.
 23. The method of claim 22, wherein a second column of a secondmatrix of the at least two co-phasing matrices provides higher gain forthe second transmission layer than the gain provided by a first columnof the second matrix for the first transmission layer.
 24. The method ofclaim 18, wherein the at least two co-phasing matrices are generated bya phase rotation upon a base matrix formed with a co-phasing factorobtained from the co-phasing information.
 25. The method of claim 24,wherein the base matrix for single-layer transmission is formed by a 2×1vector, a first element of which is equal to 1, and a second element ofwhich is equal to the co-phasing factor.
 26. The method of claim 24,wherein the base matrix for dual-layer transmission is formed by a 2×2matrix, a first element of a first column being equal to 1, a secondelement of the first column being equal to the co-phasing factor, afirst element of a second column being equal to 1, and a second elementof the second column being the negative of the co-phasing factor. 27.The method of claim 24, wherein, in case of more than two layertransmission, the more than two layers are divided into dual-layergroups for even number of layers, and are divided into dual layer groupsplus an additional layer for odd number of layers, and wherein at leasttwo co-phasing matrices are generated per dual layer group.
 28. Themethod of claim 24, wherein, if two co-phasing matrices are generatedfor two layers transmission, columns of the second matrix correspond tointerchanged columns of the first matrix.
 29. The method of claim 24,wherein if four co-phasing matrices are to be generated for two layerstransmission, then columns of a third matrix correspond to interchangedcolumns of a first matrix, and columns of a fourth matrix correspond tointerchanged columns of a second matrix. 30.-34. (canceled)
 35. Awireless device for receiving transmissions from a network node foradaptive co-phasing in an Active Antenna System, AAS, the wirelessdevice comprising processing circuitry including a processor and amemory, the memory containing instructions executable by the processorto configure the wireless device to: one of provide co-phasinginformation and signal at least one uplink reference signal fordetermining co-phasing information; receive at least one transmissionthat is based on at least two co-phasing matrices applied to one of atleast two resource structures, the at least two co-phasing matricesbeing based on the one of provided co-phasing information and signaledat least one uplink reference signal, the at least two resourcestructures being one of at least two physical resource blocks, PRBs, andat least two resource elements, Res; and process the at least onetransmission. 36.-41. (canceled)
 42. A method for a wireless device forreceiving transmissions from a network node for adaptive co-phasing inan Active Antenna System, AAS, the method comprising: one of providingco-phasing information and signaling at least one uplink referencesignal for determining co-phasing information; receiving at least onetransmission that is based on at least two co-phasing matrices appliedto one of at least two resource structures, the at least two co-phasingmatrices being based on the one of provided co-phasing information andsignaled at least one uplink reference signal and the at least tworesource structures being one of at least two physical resource blocks,PRBs, and at least two resource elements, REs; and processing the atleast one transmission. 43.-48. (canceled)